Field of Invention
This invention relates to climate control systems for buildings used to house animals, and more particularly to a method for automatically configuring the and substituting equipment in the climate control system.
Description of Related Art
In buildings that are used to house animals such as poultry, swine or livestock, it is important to maintain a desired building climate. A well-controlled environment involves monitoring and regulating the temperature, relative humidity and air quality in the building. For example, properly controlled temperatures enable animals to use feed for growth rather than for body heat. A properly heated animal house results in lower feed costs and increased animal productivity. Additionally, control over the level of humidity in the building is necessary because excess humidity contributes to animal discomfort and promotes the growth of harmful air born bacteria that can cause respiration diseases. Having an elevated humidity level in the animal house may also lead to more frequent changes of bedding and litter which increases production costs.
To maintain the proper climate in the animal building, various heaters and ventilation fans are used as necessary to maintain the desired temperature and humidity. It is known to use a control unit to automatically control operation of the heaters and ventilation fans located within the building. Sensing devices, such as temperature sensing devices, are used to provide the necessary information to the control unit to enable such automatic control. Improper operation of any of the heaters or ventilation fans can lead to undesirable and even dangerous conditions in the animal budding.
Configuration of a climate control system for protein applications is a cumbersome task that involves a great deal of knowledge of animal husbandry, protein equipment and systems, and control philosophies and technology. Control systems typically manage many diverse functions, such as heating, cooling, ventilation, feeding, and watering, each of which requiring significant effort to configure. Even the most skilled person is prone to making mistakes or forgetting something when configuring such a complex system. Assuming the system does get configured properly, it is usually a long, time-consuming task involving several steps.
First, the user must program the controller to tell it what equipment (fans, inlets, feeders, temperature probes, etc.) is physically connected to the device, and how it is connected. Next, the user must configure the detailed parameters for each function. This is the time-consuming portion, and where the industry knowledge is transferred to the controller. For example, in a poultry application, the controller may be controlling lighting. After the user first tells the controller which output is used for lighting, he must then program how the lights should work. This is typically done my creating a lighting program or “curve”, which consists of a series of table entries where for a specific age of the birds, a light on/off/intensity setting is set. The user configures as many table entries as he feels is required to properly grow the birds.
Once the lighting program is set, the user would then have to go through a detailed configuration effort for each system to be controlled. For example, next, the user might configure heaters. Then he might configure feeders or ventilation.
In protein growing industry, a large amount of application specific actuators are used for building control and automation. The animal living environment control is life-critical; improper ventilation can lead to poor herd performance and animal death. Equipment fault happens often, without warning and at any time. Quickness and automated reaction to a failure is an asset for both the animals and the site owner. Protein growing buildings are designed to fulfill the needs of animals from their birth to their shipping to the next step of the process throughout the year; HVAC (heating, ventilation and air conditioning) equipment can heat, dry, cool, humidify and move air as needed. Specific equipment is used for specific conditions in such a way that actuators get segregated in a set of discrete operating conditions to fulfill the vast set of ventilation needs. The new PVX system breaks the rules so that the different sets of equipment are seen as resources to achieve an overall goal; maintain proper living and growing conditions. By sensing operating current of each piece of equipment (and potentially aggregating the information with other data) the system can discriminate faulty and good actuators. Knowing an actuator has failed another similar device is used to achieve the overall goal. The important part of the invention is there is no redundant piece of equipment waiting for a failure to be turned on, it is really another piece(s) of equipment normally used in different conditions which are used in a different way to accomplish the task of the failed equipment.
Devices in protein raising barns are part of a sub system and used in specific building state and operating conditions. Although small fans are used in the so-called minimal or sidewall ventilation and tunnel fans for tunnel ventilation, one can replace the other in certain circumstances. Looking at fans as “ventilation units” and knowing their position in a building, a controller can calculate what is the ventilation contribution of a fan according to operating conditions and decide which equipment to use in order to temporary replace another failed equipment and this with minimum loss of performance.
The principle can be extended to other types of actuators; an air inlet that fails to open can be backed up by other similar air inlet which is normally closed in current operating conditions if the overall effect of providing more air is better than a modification of air mix or air flow pattern.
To achieve this goal, key characteristics and operating parameters of actuators need to be known and measured to detect failure and confirm backup measures have been applied. Characteristics are either entered by user for non-listed devices or read from a database of known existing equipment. The key measured parameter is amp draw and motor angular velocity (RPM) when available. An out of range amp draw can mean a broken mechanical link (low amp draw) or jammed equipment such as a blocked rotor (high amp draw). Depending on the situation it is advisable to turn of the failed equipment (to protect it from further damage) and to use another similar (or less similar) equipment to achieve the same goal while raising an alarm to warn the user.
This concept is extended to a failure of the controller output itself; a failed relay or contactor can be detected and similar or calculated backup equipment can be turned on via other still good outputs. In fact, it, may be impossible to discriminate if a failure originates from the controller output, the wiring or the actuator itself but it is almost always possible to discriminate a normal operating device from a failure and to take backup actions.
In previous systems, equipment such as fan are hardwired to an input which is assigned a dedicated function (i.e. this output is a tunnel fan which should be turned On when room temperature is greater than 85° F.). Some controllers are capable of measuring amp draw and will raise an alarm however they do not backup the failed actuator with any other piece of equipment. Other controllers make it easy for a user to disconnect a device from a failed output and to reconnect it to another known good output. None however automatically take backup actions, they would simply raise an alarm. It is desired to have a climate control system that will allow the user to quickly set up a complex system with very little interaction or knowledge.